Greg Norman was confined to bed under medical supervision and "as sick as a dog" after pulling out of the Australian PGA Championship on the Sunshine Coast after just two holes.
Making a rare tournament start, 57-year-old former world No.1 Norman made bogeys at his first two holes at the Palmer Coolum resort course on Thursday before departing for his room with what tournament officials said was suspected food poisoning.
"He is quite ill, we understand," said PGA of Australia chief executive Brian Thorburn.
"He is getting medical attention. We wish him a very speedy recovery this morning.
"It's a great shame it happened at this moment.
"I haven't spoken to him. I have spoken to his manager and I have spoken to the guys who saw him this morning.
"They're all facilitating medical treatment.
"One person described him as being as sick as a dog.
"I think Greg was trying to soldier through and clearly it wasn't possible."
Norman was one of the tournament's main drawcards along with British Open winner Darren Clarke and South African Rory Sabatini.